Apparatus and process for neutralizing acid mine drainage water



July 28, I964 EQBAER TA f 3,142,639

APPARATUS AND PROCESS FOR NEUTRALIZING ACID MINE DRAINAGE WATER FiledMarch 10, 1961 6 Sheets-Sheet 1 #4 W #7 I x W492 l 2 Fig. i

CHARLES E. 345/? smrono A. KELSEY g 33 BY 4 ATTORNEY y 23, 1964 c. E.BAER EIIAL 3,142,639

APPARATUS AND PROCESS ,FOR NEUTRALIZING ACID MINE DRAINAGE- WATER FiledMarch 10, 1961 e sheets -shee'c 2 INVENTORS 'bHARL 5s E. BAER smvrono A.KELSEY ATTORNEY 3,142,639 APPARATUS AND PROCESS FOR ,NEUTRALIZING ACIDMINEVDRAINAYGE WATER Filed March 10, 1961 July 28, 1964 c. E. B AERETAL' e Sheets-Sheet s a W I m a Fa Z M m l v n H m 1 s n n K .4 on p Z.

n T. a w V 1 5' kw m?) m m a INVENTORS GHARLES E. BAEI? V/Bk 0 TOQ 56SANFORD A. KELSEY ATTORNEY July'28, 1964 c. E. BAQER ETAL 3,142,639

APPARATUS AND PROCESS FOR NEUTRALIZING ACID MINE DRAINAGE WATERFiledMarch 10, 1961 6 Sheets-Sheet 4 INVENTORS 48 Charles E. BueraSunford'A.Kelsey 4 ATTORNEY July 28, 1964 c. E. BAER ETAL 3,142,639

APPARATUS AND PROCESS FOR NEUTRALIZING ACID MINE DRAINAGE WATER 6Sheets-Sheet 5 Filed March 10, 1961 INVENTORS Mil.

Charles E. Boer 8 FIGJ3. Sanford A. Kelsey ATTORNEY United States Patent3,142,639 APPARATUS AND I'RGCESS FOR NEUTRALKZKNG ACE MENE DRAINAGEWATER Charles E. Baer, 22G Dufi Road, Monroeyille, Pa., and

Sanford A. Kelsey, Grove City, Pa; said Kelsey assignor to Otis V.Miller, Traiford, Pa.

Filed Mar. It), 1961, Ser. No. 94,941 Claims. (Cl. 210-60) The presentinvention relates to Apparatus and Process for Neutralizing Acid MineDrainage Water and has for an object the provision of an apparatus ofthis type which will neutralize acid mine drainage water to the extentnecessary to meet the legal requirements before it can be dischargedinto the clean streams.

This invention is a continuation-in-part of our application for patenton an apparatus and process for neutralizing acid mine drainage water,Serial No. 476,322 filed December 20, 1954 now abandoned.

Some States, for example, Pennsylvania, have a law to the eifect that noacid mine drainage shall be discharged into the clean streams of theState.

The water draining from bituminous coal mines in Western Pennsylvanianearly always contains sulfuric acid. This acid is formed by theoxidation of the sulfur occurring in the coal and in the rock and clayfound above and below the coal seams. This sulfur is in part combinedwith the coal, but by far the greater part is a sulfide of iron, knownvariously as fools gold, pyrite, iron pyrites, or sulfur balls. In thepresence of water, and under the influence of oxygen in the air of themine, the sulfur is oxidized and, still combined with iron, dissolves inthe water as copperas, more properly called ferrous sulfate.

Flowing from the mine, and still in the presence of air, and sometimesunder the influence of other agents, the copperas is oxidized to ferricsulfate. The iron after this oxidation has a weakened aflinity forsulfuric acid, and in various forms is partially separated as asediment, brownish yellow in color, frequently called yellow boy.Sulfuric acid, accompanied by some iron, remains in the water. In somecases in Pennsylvania there is enough limestone in associated rocks toneutralize the acid almost as rapidly as formed, whereupon the waterflowing from the mine may be neutral or have even the natural alkalinityof ground Water. But the rocks and clays of the Pennsylvania coal seamsseldom are of alkaline character, so that acid drainage prevails in mostof the mines of the Commonwealth of Pennsyl- Vania.

It is an object of the present invention to provide a machine and aprocess which can be used to neutralize acid mine drainage water at bothdeep mines and strip mines where bituminous coal is mined and also atother desired locations.

While electricity may be used as the source of operating power at bothdeep and strip mines, yet in many instances available sources ofelectricity are remote, especially to the strip mines, in view of whichfact another object is to provide the invention in one or more formswhich do not require the use of electrical power for operation.

Definitions To neutralizeIn this case, it is desired to change the acidwater in acid mine drainage water to an alkaline water.

When a water is neutral the acidic and alkaline substances in the waterbalance or cancel each other.

AlkalinityThe condition of Water containing dissolved alkalinesubstances, like lye.

The acid in acid mine drainage water is sulphuric acid, H 80 3,1425%Patented July 28, 1964 "ice Another object of the present invention isto provide a machine of this character which has been designed to usehydrated lime as the neutralizing chemical and which will operateunattended for as long as twenty-four hours when it may be necessary toreplenish the supply of lime or lubricate the suction pump.

A further object of the present invention is to provide a device of thistype which can be operated at a very low cost, even as low as fiftycents per day so that mines now closed or that would be closed onaccount of the problem of acid mine drainage water can resume operationsor remain in operation.

The present invention aims to provide an apparatus and a process whichdoes not require the services of a highly trained technician but whichcan be operated by a person of ordinary skill.

In one of its broadest aspects the present invention contemplates theprovision of an apparatus for neutralizing acid mine drainage watercomprising a mixing container, means for supplying a neutralizing agentto said container, means for initially conducting the water to saidcontainer and subsequently conducting some of the neutralized water tosaid container and discharging the remainder of the neutralized water toa settling basin or the like.

More specifically, the present invention contemplates the provision ofan apparatus for neutralizing acid mine drainage water comprising acabinet, a hopper for receiving hydrated lime pivotally mounted Withinsaid cabinet, means for vibrating said hopper, a feeder trough forreceiving lime from the hopper, means for vibrating said trough, a.mixing tub supported by said cabinet positioned to receive lime fromsaid trough, a strainer adapted to be positioned in the water to betreated, a discharge hose connecting said tub to said strainer, anintake hose having one end connected to said strainer, a pump having itsintake side connected to the other end of the intake hose, a deliveryhose connected to the delivery side of the pump and to the tub, and adischarge hose having one end connected to the delivery side of the pumpand its opposite end free.

It is an aim of the present invention to provide a device of thischaracter in which the amount of the neutralizing agent being fed to thecontainer may be controlled.

It is also aimed especially in that form of the invention which does notrequire electrical operation, to include a novel means for so feedingthe lime that it is less apt to become damp and lumpy and will feed inregular amounts continuously.

A further aim of the present invention is to provide means fortransporting the apparatus from one location of use to another location.

The present invention contemplates the provision of a process forneutralizing acid mine drainage water com prising the steps ofintroducing the drainage water into a container, supplying aneutralizing agent to the container, agitating the agent and water,withdrawing the mixed agent and Water, mixing the mixture withadditional water to be neutralized and conducting some of the furthermixture to the container and discharging the remainder thereof to asettling basin.

With the foregoing and other objects in view, the invention will behereinafter more fully described and more particularly pointed out inthe appended claims.

In the drawings in which the same parts are denoted by the samereference numerals throughout the several views,

FIGURE 1 is a perspective view of the apparatus constructed inaccordance with the present invention,

FIGURE 2 is a sectional view taken on the line 2-2 of FIGURE 1,

sneaeao FIGURE 3 is a sectional view taken on the line 33 of FIGURE 2,

FIGURE 4 is a sectional view taken on the line 4-4 of FIGURE 3,

FIGURE 5 is a sectional view taken onthe line 5-5 of FIGURE 3,

FIGURE 6 is a sectional view taken on the line 66 of FIGURE 3,

FIGURE 7 is a side elevational view of the left side of the device,

FIGURE 8 is a rear elevational view of the same,

FIGURE 9 is a diagrammatic view of the pump and the electric circuit,

FIGURE 10 is a fragmentary side elevational view of the device withparts in section and showing a sled attached thereto,

FIGURE 11 is a fragmentary rear elevational view of the same,

FIGURE 12 is a perspective view of a modified form of the inventionparticularly adapted for use in strip mining at locations remote to anavailable source of electricity,

FIGURE 13 is a view partly in side elevation and partly in verticalsection to disclose details of the modified form of FIGURE 12,

FIGURE 14 is a cross-sectional view taken on the line 1414 of FIGURE 13,

FIGURE 15 is a vertical sectional view taken through the mixer on theline 15-15 of FIGURE 14, and

FIGURE 16 is a detail elevation of the hammer and operating mechanismwhich knocks against or vibrates the lime-containing hopper in themodified form.

Referring more particularly to the drawings, 10 indicates a cabinet, 11a mixing tub or container, 12 a discharge hose or pipe having one endportion extending through the front wall 13 of the tub and extendingdownwardly within the tub with its open end terminating a short distanceabove the bottom 14 of the tub, for example, one and one-half inchesfrom the bottom. The opposite end of the hose 12 is connected to one endof the strainer 15 which is disposed in the acid mine drainage water 16.The opposite end 17 of the strainer is open to receive the water 16.

One end of an intake hose or pipe 18 is connected to the strainer 15intermediate its ends and the opposite end of the hose 18 is connectedto the intake side of the suction pump 19 which may be a conventionaltype of selfpriming centrifugal pump.

The pump B may be operated by a suitable source of power 20. The pumpand source of power may be mounted on a mobile frame 21 having groundwheels 22 and a supporting post 23 for resting on the ground 24. Adischarge hose or pipe 25 has one end connected to the delivery side ofthe pump and its opposite end is free and open and discharges into asettling basin 26.

A valve 27 controls the flow from the delivery side of the pump to theopen end of the pipe 25. A delivery hose or pipe 28 has one endcommunicating with the discharge pipe 25 through a connection 29 locatedbetween the valve 27 and the delivery side of the pump. The opposite endof the hose 28 opens into the tub 11, laterally and adjacent the bottom14 thereof. A valve 30 controls the flow of fluid from the hose 25through the hose 28 into the tub 11. A short pipe 31 has one endcommunicating with the interior of the tub 11 adjacent the bottomthereof and its opposite end connected to the hose 12.

The cabinet 10 comprises four vertical corner members 32 which may be ofangle iron formation in cross-section. The lower ends of these cornermembers may be connected by rectangular hollow base members 33 to whichthey may be secured by welding or the like. The corner members 32 may beadditionally braced or reinforced by intermediate brace members 34 whichmay be of angle iron shape in cross-section and to which the cornermembers may be welded. At their upper end portions the corner members 32may be interconnected by upper brace members 35 of angle iron shape incross-section to which the corner members may be secured by welding. Thecabinet also comprises four sheets of material 36, such as metal or thelike, which are secured as by welding to the corner members 32, the basemembers 33 and the upper brace members 35 to form an enclosure.

The front wall 37 has its lower portion cut away for receivingtherethrough the tub 11, the major portion of which is housed within thecabinet 10. The tub is secured in position by being welded to thelowermost intermediate brace 34, as indicated at 38 and illustrated inFIGURE 6 of the drawings. The portion of the tub 11 which projectsoutwardly beyond the front wall 37 of the cabinet is covered by a lid 39which is hinged as at 40 to the front wall of the cabinet.

A hasp 41 is provided on the front wall 13 of the tub and extendsthrough a suitable opening of the lid 39 to receive a padlock by whichthe lid 39 may be locked against unauthorized entry. The front wall 37of the cabinet is provided with a ladder 42 and a hand-hold 43 by meansof which access may be had to a trap door 44 which covers an opening 45formed in the top 46. The trap door 44 may be suitably hinged to the top46 and may be locked in any conventional manner against unauthorizedentry. A pair of eye-loops 47 are secured to the top 46 of the cabinetfor receiving hooks of a derrick or the like, by means of which thecabinet may be moved from place to place.

A cone-shaped bin or hopper 48 is mounted for swinging movement withinthe cabinet on a pivot rod 49. The pivot rod 49 extends transversely ofthe cabinet and its opposite end portions extend through plates 50 whichare secured as by welding or the like to the upper brace members 35. Theswinging movement of the hopper 48 is regulated by a coil spring 51, oneend of which is attached to an eyebolt 52 secured to a nut 52a which iswelded to the rear wall of the hopper 48. The opposite end of the spring51 is fastened in the eye of an eyebolt 54 which is held tight to therear wall 55 of the cabinet by suitable locking nuts 54:: and 54b on theeyebolt 54 inside and outside of the cabinet. The tension of the spring51 will be regulated by adjusting the nuts 54a and 5412.

In order to vibrate the hopper 48, an electric vibrator 56 of aconventional type is secured in any appropriate manner to the rear wallof the hopper. The electric vibrator 56 is controlled by a conventionaltype of vibrator control 57. Access may be had to the vibrator 56 andits control through a door 58 which is hinged as at 59 to the left sidewall 60 of the cabinet. An apertured strap 61 is secured to the door 58and receives therethrough a hasp 52 carried by the side wall 60 andwhich is adapted to receive a padlock by which the door 58 is securedagainst unauthorized opening.

A discharge trough 63 is disposed below the lower restricted open end ofthe hopper 48 and is inclined downwardly toward the mixing tub 11. Thetrough is held in this inclined position by a vibrator block 64 which isresiliently mounted upon four coil springs 65 which in turn aresupported by a shelf 66 which may be welded to the rear wall of the tub11. The rear end portion of the bottom of the trough 63 may be securedto the upper surface of the block 64 and the forward end portion of thetrough is supported by a substantially L-shaped bracket 67 which issecured by welding or the like to the inner face of the rear wall of thetub 11.

The bracket 67 also serves as a splash guard to prevent splashing of thefluid over the top of the tub when the lime falls into the tub.

In order to adjust the set of the hopper 48 for fast or slow feed, aneyebolt 96 has its eye end fastened in a nut 91 Welded to the outside ofthe Wall of the hopper and its other end screw threaded and extendingfreely through a suitable opening 92 in the front wall 37 of the cabinetto receive a nut 93 thereon. It will be noted from FIGURE 3 of thedrawings that the bottom of the discharge trough 63 slopes downwardlytowards the front wall 37 of the cabinet. Accordingly, when the hopperis pulled toward the front wall 37 of the cabinet the space between thebottom of the trough and the discharge end of the hopper is increasedand the lime or other material in the hopper is fed faster. On the otherhand, when the hopper is moved towards the rear wall 55 of the cabinetthe distance between the bottom of the trough and the discharge end ofthe hopper decreases and the lime is fed slower. The position of thedischarge end of the hopper with respect to the bottom of the trough isdetermined by the position of the nut 93 on the eyebolt 90. As the nut93 is tightened or drawn up on the eyebolt 91), it pulls the hopper 48toward the front wall 37 and when the nut 93 is screwed outwardly on theeyebolt the spring 51 pulls the hopper towards the rear wall 55 of thecabinet. The spring 51 holds the hopper in any position to which it isadjusted by the nut 93 so that it is necessary to provide only one nuton the eyebolt 90.

A float chamber 68 is formed by the rear wall of the tub 11, rear wall69, side wall 70 and top and bottom wall 71 and 72. The float chamber 68communicates with the interior of the tub 11 by an aperture 73 formed inthe lower portion of the rear wall of the tub. A float 74 is positionedwithin the chamber 68 and has an upwardly extending stem 75 whichcarries movable contacts 76 which cooperate with fixed contacts 77 of aswitch 78. The switch 78 is carried by an L-shaped bracket 79 which issecured to the rear wall 69 of the chamber 68. The fixed contacts areconnected to a suitable source of electric current and also to thesource of power 20 for the pump 19 by means of cables 80. The cables 80are also connected to the vibrator 56 by means of leads 81. Aconventional type of mercury switch could be substituted for the switch78.

cabinet. This door may be locked in any conventional manner.

In the operation of the device, hydrated lime will be placed in thehopper 48, which could have a capacity of 800 pounds. The vibrator 56will keep the hydrated lime from sticking to the sides of the hopper andthe lime will fall upon the feeder or trough 63 and then drop intoiron-containing water 16 in the mixing tub. At this time the pump 19will be operating and water will enter the lower portion of the tub 11through the hose 28. This entry of the water will cause a swirlingmotion of the water in the tub which mixes the lime with the water andstarts the neutralization process.

When the tub is substantially full the water will be siphoned out of thetub through the discharge hose 12 and through the short pipe 31. Whenthe mixing tub is almost empty, that is, when the water is almost oneand one-half inches from the bottom of the tub, the siphon action stopsand the tub begins to fill again. When the water leaves the tub it flowsthrough the strainer 15 and the hose 18 into the intake side of the pump19. The water which is then mixed with the lime will then go through thesuction pump and a portion of it will be deposited in the settling basin26, the remainder of the mixed lime and water 16 will be permitted tostand long enough in the settling basin for the iron to settle outbefore the water is allowed to be discharged to the receiving cleanstream.

When the apparatus is started, the water taken through the pump has notbeen neutralized and should not be allowed to flow to the settling basin26. Accordingly, the valve 27 will be closed and the valve 3%) opened topermit all of the non-neutralized water to flow through hose 28 into thetub 11. When the tub is filled the valve 27 will be opened and the valve30 will remain open. The

neutralized water from the tub will be mixed with the water 16 from thesump which is drawn into the hose 18 through the open end 17 of thestrainer.

In case the water stops coming into the tub, the float 74 will fall inthe chamber 68 with the receding water and will disengage the contacts76 and 77 to break the circuit and stop the engine 213, pump 19 and thevibrator 56.

The continuous flow of water from the tub 11 through the pipe 31prevents any sediment from collecting on the bottom of the tub. Thismachine will operate in temperatures around 10 below zero degreesFahrenheit.

But all the time while mixing tub 11 is filling up and emptying, thewater is running out of the mixing tub through pipe 31. From the time ittakes for the mixing tub to fill up and empty, if the water did not keepflowing out of the mixing tub through pipe 31, then there would be thisperiod of time when the acid water 16 being pumped from the sump wouldnot be neutralized. This continuous flow of water through the pipe 31fills the gap between the time it takes for the mixing tub to fill andempty and therefore accomplishes the continuous neutralization of theacid Water 16 being pumped from the sump.

Under some conditions the drainage point for the mine drainage waterchanges from one location to another and it is necessary to shift theapparatus. This is especially true in a strip mine in which the stripcuts may be a mile or more long. In order to facilitate the requiredmovement of the apparatus, a sled generally indicated at 100, in FIGURES10 and 11 of the drawings is provided. The sled comprises a pair ofrunners 101 which may be in the form of I-beams and a plurality of crossbeams 102 which may be of channel shape in crosssection. The runners 101are secured to the bottom of the cabinet 10 and the tub 11 adjacent theopposite sides thereof. The outside edge of each runner is flush withits side of the cabinet and tub. The cross braces 102 extend across thespace between the runners in spaced apart substantially parallelrelation and have their opposite end portions welded to the Webs andinner flanges of the runners.

The apparatus may be moved from place to place in a coal strippingoperation by pulling it on the sled by a truck or bulldozer. When it isdesired to move the apparatus from one operation to another operationwhich is a substantial distance away, for example, two miles or moreover a dirt or hard to top road, it is intended that the apparatus beloaded on a truck or trailer and moved to the new location.

It is clear from the above description that the present inventionprovides an apparatus for neutralizing acid mine drainage watercomprising a mixing tub, means for supplying a neutralizing agent tosaid tub, means for conducting the water to the tub for mixing with saidagent, means for subsequently withdrawing the mixture from the tub andreturning some of it to the tub and discharging the remainder to asettling basin or the like.

Referring now to one form of the invention which does not require theuse of electricity for operation, that is the form of FIGS. 12 through16, the lower portion or" a suitable vertical enclosure or housing 100is located above a mixing container or basin 101 which is eitherintegral with or separate from the container. Such receptacle 101 issupported on an appropriate base 102 from which uprights or risers 101extend to confine the container thereon. Said container at the top has afiller opening with which the hinged or other replaceable or removableclosure 103 is associated. Said container 100 has a suitable door 164hinged at 104 in place over the doorway at 105, and is adapted to belatched or locked closed as at 106.

Reverting to the mixing basin 101, it has rigidly mounted therein acentral vertical bearing rod 106 (FIG. 15) on which a suitable mixingrotor 107 is journalled,

said rotor having an inverted hollow hub 108 closed at its top andcontaining a ball or tapered hearing at 109 engaging and suspending therotor from the top of said rod 106. The mixing rotor 107 has mixingvanes or blades 110 radiating from the hub 108.

Slightly above said hub 108 is a spider consisting of crossed structuralor reinforcing bars 111 in and centrally of which a post 112 isjournalled. Post 112 rises from a cap 113 fastened onto the upper end ofhub 108 whereby it will rotate with the rotor.

Within the housing 100 and occupying the upper portion thereof is agenerally conical hopper 114 which is pivotally, flexibly or otherwisesuspended from the top of the houisng 100 at 115. Said hopper 114 isadapted to contain a supply of hydrated lime and is open at the bottomwhereby the hydrated lime will feed by gravity onto a spreader plate 116fast on the post 112 above the bars 111. Said hydrated lime is adaptedto be centrifugally dispersed by or spread from the plate 116 and fallfrom its periphery into the mixing basin or container 101. The post 112has an arm or agitator 117 extending upwardly and diagonally therefrominto the hopper so as to agitate or scrape the hydrated lime at saidoutlet opening through the rotation of rotor 107. The amount or quantityof hydrated lime which may be discharged from the plate 116 is regulableaccording to the position of an arm 118 which is adjustable radially ofthe plate, the same being pivoted at 119 (FIG. 14) to one of the bars111 and adjustably fastened by a suitable bolt 120 carried by the bar118 and movable in an arcuate slot 121 of an arm 122 fastened to one ofthe bars 111.

The acid mine drainage water passes through the mixing basin orcontainer 101 and is neutralized therein by admixture or solution withthe hydrated lime.

One end of a discharge conduit or hose 123 extends from the mixing basinor container 101 (FIG. 12) and its opposite end is connected to astrainer 124 which is disposed in the acid mine drainage water 125, theopposite end 126 of the strainer being open to receive the water 125,and intake conduit or hose 127 is connected to the strainer 124intermediate its ends, and the opposite end of the conduit 127 isconnected to the intake side of a suction pump 128 which may be aconventional mobile type of self-priming centrifugal pump, usuallyoperable by steam, an internal combustion engine or any equivalent 129as in connection with the pump 19 of the previous form. A dischargeconduit or hose 130 has one end connected to the delivery side of thepump 128 with its opposite end free and open to discharge into asettling basin 131.

A valve 132 controls the flow from the delivery side of the pump 128 tothe open end of the conduit 130. A delivery conduit or hose 133 has oneend in communication with the discharge pipe 130 through a connection134 located between the valve 132 and the delivery side of the pump. Theopposite end of the conduit 133 opens into the basin or container 101adjacent the bottom thereof, and a vlave 135 controls the flow of fluidfrom the conduit 130 through the conduit 133 into said basin orcontainer. A short pipe 136 functioning like pipe 31 in the first formhas one end communicating with the interior of the mixing basin orcontainer 101 adjacent the bottom thereof and its opposite end connectedto the conduit 123.

Said mixing basin or container 101 has a normally closed valve drainoutlet 137. The fluid which enters the mixing basin or container 101through the action of pump 128 has considerable force and so actsagainst the blades 110 as to rotate the mixing rotor 107. Rising fromeach or a suitable number of said blades 110 and equidistantly spaced inan annular path, are lugs 138 which intermesh or move into and out ofthe spaces provided by a wheel 139 having a suitable number of tines 140radiating from a vertical shaft 141 journalled in and suspended from asuitable bearing 142 attached to 8 one of the bars 111, and alsojournalled in and suspended from another bearing 142 mounted by adiagonal skeletonized superstructure 144 suitably connected to thecontainer 101 and the bars 111 therein.

At the upper end of shaft 141 is a worm-gear 145 intermeshed with a wormgear wheel 146 mounted on a horizontal shaft 147 in turn journalled in abearing 148 carried by an upright member 149 of the skeletonizedstructure 144. Rigid on shaft 147 is a radial arm 150. Pivoted at 151 toa lug 152 fastened at the upper end of the upright member 149 is an arm153 forming part of a hammer 154 whose head 155 is generally arcuate andis provided with a lateral lug 156. Said hammer-head 155 preferablycarries a weight 157. Thus, as the arm rotates clockwise, it will at theproper times in its cycles of rotation engage the lug 15d and thus movethe left hand or free end of the hammer head upwardly and away from thehopper 114 and past lug 156 to release the same, whereupon the weight157 impels the free end of said hammer to knock against the hopper 114,and thus vibrate or agitate the same and the hydrated lime therein toassist in its discharge therefrom onto the plate 116.

Presuming operation of the modified form of FIGS. 1216 to neutralizeacid mine drainage water effected other than by the use of electricity,for instance by steam power or an internal combustion engine, the acidmine drainage water 125 is passed to the container 101 by means of thestrainer 124 126, conduit 127, pump 128 and conduit 133. Hydrated limeis supplied to the mixer or container 101 from hopper 114, agitated orvibrated by means of the hammer 155. The fluid flowing into the mixercontainer 101 will agitate the lime and water and will engage the vanes110 and operate the rotor 107 so that hub 108 through cap 113 and post112 will rotate plate 116 and agitator 117, thus facilitating thedischarge of the hydrated lime into the mixing basin, the quantity ofdischarged lime being governed through the adjustment of the arm 118.The mixed water and lime in mixing basin 101 is withdrawn from thatbasin by suction of the pump 128 siphonically acting through the pipe127, strainer 124426, and pipe 123. The mixed water and lime are mixedwith additional water drawn through strainer 124 due to the action ofpump 128. A portion of the mixture is conducted to the bottom of themixing basin 101 by way of conduit 133, and the remainder of the mixtureis discharged to a settling tank or reservoir 131 similar to that at 26of the first form of the invention.

It is obvious that various other changes and modifications may be madein the details of construction and design of the above specificallydescribed embodiment of this invention without departing from the spiritthereof, such changes and modifications being restricted only by thescope of the following claims.

What is claimed is:

1. An apparatus for neutralizing acid mine drainage water comprising acabinet, a hopper for receiving hydrated lime pivotally mounted withinsaid cabinet, means for vibrating said hopper, a feeder trough forreceiving lime from the hopper, means for vibrating said trough, amixing tub supported by said cabinet positioned to receive lime fromsaid trough, a strainer adapted to be positioned in the water to betreated, a discharge hose connecting said tub to said strainer, anintake hose having one end connected to said strainer, a pump having itsintake side connected to the other end of the intake hose, a deliveryhose connected to the delivery side of the pump and to the tub, and adischarge hose having one end connected to the delivery side of the pumpand its opposite end free.

2. An apparatus for neutralizing acid mine drainage water comprising acabinet, a hopper for receiving hydrated lime pivotally mounted withinsaid cabinet, means for vibrating said hopper, a feeder trough, forreceiving lime from the hopper, means for vibrating said trough, amixing tub supported by said cabinet positioned to receive lime fromsaid trough, a strainer adapted to be positioned in the water to betreated, a discharge hose connecting said hubto said strainer, an intakehose having one end connected to said strainer, a pump having its intakeside connected to the other end of the intake hose, a delivery hoseconnected to the delivery side of the pump and to the tub, a dischargehose having one end connected to the delivery side of the pump and itsopposite end free, and resilient means for regulating the amplitude ofthe swinging movement of the hopper.

3. An apparatus for neutralizing acid mine drainage water comprising acabinet, a hopper for receiving hydrated lime pivotally mounted withinsaid cabinet, means for vibrating said hopper, a feeder trough forreceiving lime from the hopper, means for vibrating said trough, amixing tub supported by said cabinet positioned to receive lime fromsaid trough, a strainer adapted to be positioned in the water to betreated, a discharge hose connecting said tub to said strainer, anintake hose having one end connected to said strainer, a pump having itsintake side connected to the other end of the intake hose, a deliveryhose connected to the delivery side of the pump and to the tub, adischarge hose having one end connected to the delivery side of the pumpand its opposite end free, electrically controlled means for controllingsaid hopper vibrating means, electrically controlled means for operatingsaid pump, and float means operated by the level of the water in the tubfor controlling said electric means.

4. An apparatus for neutralizing said mine drainage water comprising a.cabinet, a hopper for receiving hydrated lime pivotally mounted withinsaid cabinet and having a discharge outlet, a feeder trough having abottom inclined with respect to said hopper discharge outlet forreceiving lime from the hopper, a mixing tub supported by said cabinetand positioned to receive lime from said trough, means for setting thehopper about its pivot so as to vary the space between the hopperdischarge outlet and the inclined bottom of the trough to vary theamount of lime being fed by the hopper to the trough, a discharge hosefor connecting the tub to the drainage water, an intake hose having oneend adapted to be connected to the drainage water, a pump having itsintake side connected to the other end of the intake hose, a deliveryhose connected to the delivery side of the pump and to the tub, and adischarge hose having one end connected to the delivery side of the pumpand its opposite end free.

5. A process for neutralizing acid mine drainage water comprising thesteps of introducing the water to a container, supplying hydrated limeto the container, agitating the lime and water, positively withdrawingthe mixed lime and water from the container by suction, utilizing thesame suction to draw in additional water to be neutralized and mix itwith the mixed lime and water, and conducting some of the furthermixture to the container and discharging the remainder thereof to asettling basin.

6. A process for treating acid mine drainage water comprising mixing thewater and a neutralizing agent in a container, withdrawing the mixturefrom the container by suction, utilizing the same suction to draw inadditional acid mine drainage water to be neutralized and mix it withthe withdrawn mixture, and while the container has a neutralizing agenttherein returning part of the last-mentioned mixture into the containerand discharging the remainder thereof short of the container.

7. A process for treating acid mine drainage water comprising mixing theWater and a neutralizing agent in a container, withdrawing the mixturefrom the container by suction, utilizing the same suction of saidWithdrawn mixture to draw in additional acid mine drainage water to beneutralized and mix it with the withdrawn mixture, and while thecontainer has a neutralizing agent therein returning part of thelast-mentioned mixture into the container and discharging the remainderthereof short of the container.

8. An apparatus for neutralizing acid mine drainage water comprising amixing container, means for supplying a neutralizing agent to saidcontainer, pumping means for conducting the Water to the container formixing With said agent, means operatively associated with said pumpingmeans for subsequently sucking the mixture from the container and alsosucking in additional acid mine drainage water to be neutralized,returning some of it to the container and discharging the remainder to asettling basin, and means for rendering the subsequent meansinoperative.

9. An apparatus for neutralizing acid mine drainage water comprising amixing container, means for supplying a neutralizing agent to saidcontainer, pumping means for conducting the water to the container formixing with said agent, means operatively associated with said pumpingmeans so that unneutralized acid mine drainage Water is drawn into saidmixture by said pumping means, and means for subsequently sucking themixture from the container and also sucking in additional acid minedrainage water to be neutralized, returning some of it to the containerand discharging the remainder to a settling basin.

10. An apparatus for neutralizing acid mine drainage water comprising ahopper for receiving hydrated lime, a receptacle to receive lime fromsaid hopper, a strainer for positioning in the said water to be treated,a discharge conduit connecting said receptacle and said strainer, anintake conduit having one end connected to said strainer, a pump havingits intake connected to the other end of said intake conduit, a deliveryconduit connected to the delivery side of the pump and to thereceptacle, and a discharge conduit having one end connected to thedelivery side of the pump and its opposite end free.

11. Apparatus according to claim 10 having a mixer in said receptaclemovable through the impact of entering acid mine drainage water.

12. Apparatus according to claim 10 having a mixer in said receptaclemovable through the impact of entering acid mine drainage water, andmeans operable through motion of said mixer to vibrate or knock saidhopper to facilitate discharge of the lime therein.

13. Apparatus according to claim 10 having a mixer rotatable in saidreceptacle, and means operable through the rotation of said mixer tovibrate or hammer said hopper to facilitate the discharge of the limetherein.

14. Apparatus according to claim 10 having a mixer in said receptacle, ahub rising from the base of said receptacle on which said mixer isjournalled, operating means for said mixer, and means intergeared withsaid mixer movable to knock against said hopper to facilitate thedischarge of the lime.

15. Apparatus according to claim 10 having a mixer in said receptacle, ahub rising from the base of said receptacle on which said mixer isjournalled, operating means for said mixer, means intergeared with saidmixer movable to knock against said hopper to facilitate the dischargeof the lime, said operating means including a vertical part, a rotatablearm operable by said part, and means adjacent said hopper includinghammer mechanism operable through rotation of said arm to hammer againstsaid hopper.

16. Apparatus according to claim 10 including a mixer in saidreceptacle, and a plate to receive lime from said hopper rotatable withsaid mixer to discharge the lime into said receptacle.

17. Apparatus according to claim 10 including a mixer in saidreceptacle, a plate to receive lime from said hopper rotatable with saidmixer to discharge the lime into said receptacle, and means to regulatethe quantity of lime dischargeable from said plate.

18. Apparatus according to claim 10 including a mixer 1 1 in saidreceptacle, and a plate to receive lime from said hopper rotatable withsaid mixer to discharge the lime into said receptacle including a baradjustably movable over the plate between its periphery and axis.

19. Apparatus according to claim 10 having a mixer operable in saidreceptacle, said mixer having a vertical hub, said receptacle having apost on which said hub is journalled, frame means within the receptacle,a part rising from the hub journalled in the frame means, and a limereceiving and discharging plate carried by the said part and arrangedbelow the hopper.

20. A process for neutralizing acid mine drainage water comprising thestep of introducing the water to a container, supplying hydrated lime tothe container, agitating the lime and Water, withdrawing the mixed limeand water 1.2 from the container by suction, utilizing the same suctionto draw in a limited additional amount of the Water to be neutralizedand mix it with the withdrawn mixture, and conducting some of thefurther mixture to the container and discharging the remainder thereofto a settling basin. 1

References Cited in the file of this patent UNITED STATES PATENTS510,112 Blessing Dec. 5, 1893 1,514,336 Pruss Nov. 4, 1924 2,350,095Carlson et al May 30, 1944 2,503,878 Linn Apr. 11, 1950 2,915,463Williams Dec. 1, 1959

1. AN APPARATUS FOR NEUTRALIZING ACID AMINE DRAINAGE WATER COMPRISING ACABINET, A HOPPER FOR RECEIVING HYDRATED LIME PIVOTALLY MOUNTED WITHINSAID CABINET, MEANS FOR VIBRATING SAID HOPPER, A FEEDER TROUGH FORRECEIVING LIME FROM THE HOPPER, MEANS FOR VIBRATING SAID TROUGH, AMIXING TUB SUPPORTED BY SAID CABINET POSITIONED TO RECEIVE LIME FROMSAID TROUGH, A STRAINER ADAPTED TO BE POSITIONED IN THE WATER TO BETREATED, A DISCHARGE HOSE CONNECTING SAID TUB TO SAID STRAINER, ANINTAKE HOSE HAVING ONE END CONNECTED TO SAID STRAINER, A PUMP HAVING ITSINTAKE SIDE CONNECTED TO THE OTHER END OF THE INTAKE HOSE, A DELIVERYHOSE CONNECTED TO THE DELIVERY SIDE OF THE PUMP